airworthiness · Rule · Final rule. · Published 2012-04-25 · Effective 2012-05-30 · 77 FR 24585
Document
Document number
2012-9789
Federal Register citation
77 FR 24585
Type
Rule
Action
Final rule.
Category
airworthiness
Manufacturer
Turbomeca S.A. Turboshaft
Publication date
2012-04-25
Effective date
2012-05-30
FAA docket
Docket No. FAA-2012-0010
Abstract
We are adopting a new airworthiness directive (AD) for all Turbomeca S.A. Arriel 2B and 2B1 turboshaft engines. This AD was prompted by the discovery of non-conformities of certain power turbine (PT) blade fir-tree roots. This AD requires removing the affected PT blades from service on or before reaching a new reduced life limit for those certain PT blades. We are issuing this AD to prevent PT blade rupture, which could result in an uncommanded in-flight engine shutdown, forced autorotation landing, or accident.